Challenge 19, Team F.L.A.M.B.E.S!

31st suggestion, made by Mikey!

Marketplace Sales:

https://marketplace.tf/items/tf2/30614;5;u3015

1:

https://backpack.tf/item/3716347864 - ?

May 24th - $15.56

Keys were $1.88 that day, so 15.56 / 1.88 = 8.3 keys, rounding to 8.5.

2:

https://backpack.tf/item/3694156013

June 18th: $15.56

Keys were $1.98 that day, so 15.56 / 1.98 = 7.86 keys, rounding to 8.

3:

Can't find item history.

June 22nd: $15.56

Keys were $1.98 that day, so 15.56 / 1.98 = 7.86 keys, rounding to 8.

Other Sales:

4:

https://backpack.tf/profiles/76561198134220286#!/compare/1593043200/1593216000

https://backpack.tf/profiles/76561198841279602#!/compare/1592956800/1593043200

QS

5:

https://backpack.tf/profiles/76561198106323995#!/compare/1590969600/1591142400

https://backpack.tf/profiles/76561198311498888#!/compare/1590969600/1591056000

STN - Unusable.

6:

https://backpack.tf/profiles/76561198311498888#!/compare/1591315200/1591401600

https://backpack.tf/profiles/76561198110677513#!/compare/1591315200/1591833600

Untrace / STN

7:

https://backpack.tf/profiles/76561198110677513#!/compare/1592006400/1592265600

https://backpack.tf/profiles/76561198871163068#!/compare/1592179200/1592265600

QS

8:

https://backpack.tf/profiles/76561198871163068#!/compare/1592265600/1592352000

https://backpack.tf/profiles/76561198080909224#!/compare/1592265600/1592352000

Untrace

9:

https://backpack.tf/profiles/76561198080909224#!/compare/1592352000/1592438400

https://backpack.tf/profiles/76561198118238251#!/compare/1592352000/1592438400

Untrace

Summary of Sales:

2 @ 8 keys

1 @ 8.5 keys

Taking 8-8.5 keys.